Laser Generation of Stress Waves in Metal

Microresonator-based lasers in the two-micron range are interesting for extensive applications. Tm3+ ions provide high gain; therefore, they are promising for laser generation in the two-micron range in various matrices. We developed a simple theoretical model to describe Tm-doped glass microlasers generating in the 1.9–2 μm range with in-band pump at 1.55 μm. Using this model, we calculated threshold pump powers, laser generation wavelengths and slope efficiencies for different parameters of Tm-doped tellurite glass microspheres such as diameters, Q-factors, and thulium ion concentration. In addition, we produced a 320-μm tellurite glass microsphere doped with thulium ions with a concentration of 5·1019 cm−3. We attained lasing at 1.9 μm experimentally in the produced sample with a Q-factor of 106 pumped by a C-band narrow line laser.

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Analysis of the expansion process of cracks caused by blasting stress waves in a PMMA medium with filled defects

Materials Today Communications ◽

10.1016/j.mtcomm.2021.102396 ◽

2021 ◽

pp. 102396

Author(s):

Yanbing Wang ◽

Jiaqing Dong ◽

Zhaoyang Wang ◽

Yabin Zhao

Keyword(s):

Stress Waves ◽

Expansion Process

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An experimental demonstration of the effect of mechanical stresses on the laser generation of acoustic vibrations in various materials

Journal of Physics Conference Series ◽

10.1088/1742-6596/1697/1/012186 ◽

2020 ◽

Vol 1697 ◽

pp. 012186

Author(s):

A L Glazov ◽

K L Muratikov

Keyword(s):

Mechanical Stresses ◽

Laser Generation ◽

Acoustic Vibrations ◽

Experimental Demonstration

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Design and Analysis of a Novel Piezoceramic Stack-based Smart Aggregate

Sensors ◽

10.3390/s20226438 ◽

2020 ◽

Vol 20 (22) ◽

pp. 6438

Author(s):

Guangtao Lu ◽

Xin Zhu ◽

Tao Wang ◽

Zhiqiang Hao ◽

Bohai Tan

Keyword(s):

Resonance Frequency ◽

Electromechanical Coupling ◽

Structural Parameters ◽

Electromechanical Coupling Factor ◽

Coupling Factor ◽

Stress Waves ◽

Parallel Connection ◽

Smart Aggregate ◽

In Series ◽

Piezoelectric Wafers

A novel piezoceramic stack-based smart aggregate (PiSSA) with piezoceramic wafers in series or parallel connection is developed to increase the efficiency and output performance over the conventional smart aggregate with only one piezoelectric patch. Due to the improvement, PiSSA is suitable for situations where the stress waves easily attenuate. In PiSSA, the piezoelectric wafers are electrically connected in series or parallel, and three types of piezoelectric wafers with different electrode patterns are designed for easy connection. Based on the theory of piezo-elasticity, a simplified one-dimensional model is derived to study the electromechanical, transmitting and sensing performance of PiSSAs with the wafers in series and parallel connection, and the model was verified by experiments. The theoretical results reveal that the first resonance frequency of PiSSAs in series and parallel decreases as the number or thickness of the PZT wafers increases, and the first electromechanical coupling factor increases firstly and then decrease gradually as the number or thickness increases. The results also show that both the first resonance frequency and the first electromechanical coupling factor of PiSSA in series and parallel change no more than 0.87% as the Young’s modulus of the epoxy increases from 0.5 to 1.5 times 3.2 GPa, which is helpful for the fabrication of PiSSAs. In addition, the displacement output of PiSSAs in parallel is about 2.18–22.49 times that in series at 1–50 kHz, while the voltage output of PiSSAs in parallel is much less than that in parallel, which indicates that PiSSA in parallel is much more suitable for working as an actuator to excite stress waves and PiSSA in series is suitable for working as a sensor to detect the waves. All the results demonstrate that the connecting type, number and thickness of the PZT wafers should be carefully selected to increase the efficiency and output of PiSSA actuators and sensors. This study contributes to providing a method to investigate the characteristics and optimize the structural parameters of the proposed PiSSAs.

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ULTRAFAST LASER‐INDUCED STRESS WAVES IN SOLIDS

Applied Physics Letters ◽

10.1063/1.1653468 ◽

1971 ◽

Vol 18 (1) ◽

pp. 33-35 ◽

Cited By ~ 22

Author(s):

E. D. Jones

Keyword(s):

Stress Waves ◽

Ultrafast Laser ◽

Induced Stress

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Time-Resolved Investigation of the Molecular Chemiluminescence SrI(A2∏1/2,3,2,B2∑+→X2∑+) and the Atomic Resonance Fluorescence Sr(53P1→51S0) Following The Pulsed Dye Laser Generation Of Sr(53PJ) in the Presence of CF3I

Laser Chemistry ◽

10.1155/1995/98207 ◽

1995 ◽

Vol 16 (2) ◽

pp. 121-138 ◽

Cited By ~ 5

Author(s):

S. Antrobus ◽

D. Husain ◽

Jie Lei ◽

F. Castaño ◽

M. N. Sanchez Rayo

Keyword(s):

Ground State ◽

Branching Ratio ◽

Atomic Emission ◽

Electronic Energy ◽

Dye Laser ◽

Pulsed Dye Laser ◽

Laser Generation ◽

Buffer Gas ◽

Resonance Fluorescence ◽

Time Resolved

A time-resolved investigation is presented of the electronic energy distribution in SrI following the collision of the optically metastable strontium atom, Sr [5s5p(3PJ)], with the molecule CF3I. Sr[5s5p(3PJ)], 1.807 eV above its 5s2(1S0) electronic ground state, was generated by pulsed dye-laser excitation of ground state strontium vapour to the Sr(53P1) state at , λ =689.3 nm {Sr(53P1←51S0)} at elevated temperature (840 K) in the presence of excess helium buffer gas in which rapid Boltzmann equilibration within the 53PJ spin-orbit manifold takes place. Time resolved atomic emission from Sr(53P1→51S0) at the resonance transition and the molecular chemiluminescence from SrI(A2∏1,2,3/2,B2∑+→X2∑+) resulting from reaction of the excited atom with CF3I were recorded and shown to be exponential in character. SrI in the A2∏1/2,3/2 (172.5, 175.4 kJ mol-1) and B2∑+ (177.3 kJ mol-1) states are energetically accessible on collision by direct-I-atomic abstraction between Sr(3P) and CF3I. The first-order decay coefficients for the atomic and molecular emissions are found to be equal under identical conditions and hence SrI(A2∏1/2,3/2, B2∑+) are shown to arise from direct I- atom abstraction reactions. The molecular systems recorded were SrI (A2∏1/2→X2∑+, Δv=0, λ=694 nm), SrI(A2∏3/2→X2∑+, Δv=0, λ=677 nm) and SrI(B2∑+→X2∑+) (Δv=0, λ=674 nm), dominated by the Δv=0 sequences on account of Franck-Condon considerations. The combination of integrated m61ecular and atomic intensity measurements yields estimates of the branching ratios into the specific electronic states, A1/2, A3/2 and B, arising from Sr(53PJ)+CF3I which are found to be as follows: A1/2,1.2 × 10-2; A3/2, 6.7 × 10-3; B, 5.1 × 10-3 yielding ∑SrI(A1/2+A3/2+B)=2.4 × 10-2. As only the X, A and B states SrI are accessible on reaction, assuming that the removal of Sr(53PJ) occurs totally by chemical removal, this yields an upper limit for the branching ratio into the ground state of ca. 98%. The present results are compared with previous time-resolved measurements on excited states of strontium halides that we have reported on various halogenated species resulting from reactions of Sr(53PJ), together with analogous chemiluminescence studies on Sr(3PJ) and Ca(43PJ) from molecular beam measurements.

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